Wilhelm hefti



W. HEFTI.

CYLINDER HEAD. APPLICATION FILED FEB. 26. m9.

1,374,079. Patented Apr. 5,1921.

UNITED STATES PATENT OFFICE.

wrnnnmvr HEFTI, or WfTLFLING EN, SWITZERLAND, Ass enon TO BUSGH-SULZER BROS-DIESEL ENGINE COMPANY, on ST. LOUIS, MISSOURI, A CORPORATION OF nrrssonm.

CYLINDER-HEAD.

Patented Apr. 5, 1921.

Application filed February 26, 1919. Serial No. 279,380.

To all whom it may concern:

Be it known thatI, WILHELM Hnr'rr, citizen of the Republic of Switzerland, residing at Wiilfiingen, Switzerland, have invented the following-described; Improvements in Cylinder-Heads. j The invention concerns the construction of internaleombustion engines and apparatus subject to like thermal conditions and provides certain principles of cylinder head structure as herein described which efi'ectually eliminate the occurrenceof strains from thermal expansions and abrupt temperature on the outer cylinder wall 2 and therewithforming the usual water jacket space. In the present case the two cylinder walls are arranged with their end faces substant1ally flush, this being a preferred but not necessary relation. The cylinder head comprises an inner head wall?) forming the end inclosure'to the cylinder space andtherefore directly exposedto the'temperature therein, an outer head wall 4, a peripheral sidewall 5 of circular section and a central valvemay circulate freely in the annular space around the socket wall 6. All the valve mechanism which is desired to be mounted in thehead structure is situated in the valve socket so that between said socket and the periphery there is an annular portion of each head wall uninterrupted by passages and hence free to expand on thermal change, unlformly along every radius. The cavity oi the socket 1n the present case, accommodates a fuel injection valve 7 and an air 7 starting valve 8 both contained in a suitable valve cage 9 indicated diagrammatically in the drawing;

The inner dished is of no greater diameter than just sufficient to span and make a proper joint with the end face. of the cylinder liner 1,

' cad wall 3 which is slightly with which transverse surface the joint is made in the present case by means of a circular rib 10 which seats on a gasket held in the packing groove 11 in the liner. The said rib and groove are both disposed as close to the interior cylindrical surfaceof the liner as consistent with security and inasmuch as the rib is in the nature of a peripheral flange on head wall 3, there is no peripheral metal in the head outside the joint which is liable to thermal expansion at a different rate from the central portion of such wall; that is to say, the said inner head. wall terminates at the joint, close to the interior cylindrical space, and does not extend beyond it, in consequence of which practically the whole area of said head wall 3 is exposed on one side to the temperature ofthe combustion space and on the other to that of the cooling water, no partof the wall or head structure being in contact with, or

in heat-transferring relation to, the metal 1 of the cylinder outside the joint, as for example, at the surface marked 12. At any given moment therefore there is equality of temperature at all points of said Wall and hence an absence of temperature difference l1kely to develop thermal strains. If the head wall 3 were extended over the surface 12, as is commonly the case, the metal in such extended peripheral portion would be subjected to a different temperature and by shrinking or expanding at a difi'erent rate from the symmetrical interior part of the wall would thereby set up strains tending to crack or weaken the metal. The absence of such peripheral metal and the symmetry of the head wall as above described coiipe-rate to eliminate all these strains thereby insuring the integrity of the casting under all conditions and preserving at all times aleak tight joint with the cylinder.

The inner. head wall 3 in order to form a combustion space of the most desirable shape slopes fromthe neighborhood of the joint away from the piston so as to present a dished 0r concave face to cylinder, v

Fromthe peripheral packing rib 10, the side Wall 5 extends divergently outward to its'point of junction with the outer head wall 4, at which point it is provided with a bolt flange V 13 or equivalent attachment means adapted for engagement by the belts or studs 1a by which the head is secured in place.

'Suchbolts are threaded to the outer cylinder wall 2 substantially in the transverse plane of the oint groove 11 and extend free from that plane to the flange 13 thereby leaving a space. around the joint which is open to at- Ymosphere; The'divergence oi the side wall 5 brings the bolt flange l3 into'proper alinc- .ment with the bolts and the cylinder wall 2 and also provides an ample apacity of interior water space which is specially desir- ,able when the valve-socket contains several 'yalves.' The divergent angle of the sidewall s also effective in directly transmitting the clamping pressure of the bolts 14: to'the joint groove ll which pressure, it will be observer,

shape of the head structure and the details of thisand the liner 1011M}. and the connecting means-are important features of the invention' butare manifestly subordinate to the mal strains in said structure. "2. The combination with a cyl nder, of a wateracketed head comprising a single censymmetrical disposition of metal. of the head I walls and the elimination of abrupt temperature differences, the relation of which has now been explained, and no limitation 1s to be understood as applying to this invention in respectto such or other incidental fea ,tures except as definitelyrmentioned in the .follovving'claims. V

Claims: 1; The combination with a cylinder, of a water-j acketed head structure symmetrically formed about-a: central space orcavity which accommodates all thecylinder-head valve mechanism; the inner head wall making a joint againsta transverse surface of the cyl inder: andbeingdevoid of peripheral metal outside the joint capable of developing thertral valve socket containing all the cylinderhead valve mechanism and an innerrhead :wa'll making oint with a transverse surface of the cylinder and attachment meanson the head, removed from said joint, for connecting; the head to the cylinder. 3: The combination with a cylinder,- of a removable head making-joint with the end the interior of the face of the cylinder near the interior surface thereof and being devoid of peripheral metal or lo the joint capable of developing thenial strains in the head structure, and connection members extending lfroni the region oi: said joint to the outer end of the head structure.

4:. The combination with an outer cylinder wall having a liner seated thereon and forming a water-jacket space therewith, of a removable water-jacketed head making joint with the liner and being devoid of peripheral metal outside the joint capable of developing thermal strains in the head structure and connection. members extending from the outer cylinder wall in the region 0'? said joint to the outer end of the head structure.

5. The combination with a cylinder, of a. water-jacketed cylinder head comprising inner and outer hca d walls united solely by a single valve-socket wall and a. peripheral side wall, the inner head wall making joint with the cylinder end and being devoid of peripheral metal outside the joint capable of developing thermal strains in the structure.

6. The combination with a cylinder, of a water-jacketed cylinder head structure coni- .prising'an inner head wall making joint with the cylinder end and a peripheral side toward the outer wall of said head structure.

7. The combination with an outer cylindrical wall and a liner seated thereon, of a water-jacketed head comprising an inner head. wall making joint with the liner, a pcripheral side wall (liverging from the joint, a bolt flange near the wide part of the side wall, and means for securing the flange to the outer cylinder wall.

8. The combination with a cylinder, of a water-jacketed cylinder head com 'irising innor and outer head walls united solely by a single valve-socket wall and a 'ieripheral side wall, the inner head wall making joint with the cylinder end, being devoid 01f peripheral metal outside the joint capable of developing thermal. strains in the structure, and sloping from the neighborhood oi? the joint away from the piston. so as to present a dished or concave face to the interior of mechanism, the inner head wall being dished or concave toward the interior of the cylinder, making a joint against a transverse surface 01": the cylinder and being devoid of peripheral metal outside the joint capable of developing thermalstrains in said structure.

10. The combination with an outer cylinder wall having a liner seated thereon and form ng a wateracket space therewith, of a removable water-jacketed head makingjoint members extending from the outer cylinder with the liner and being devoid of periphwall in the region of said joint to the outer eral metal outside the joint capable of deend of the head structure. 10 velopingtherlnal strains in the head struc- In testimony whereof, I have signedthis 5 ture, the seat of the joint with the liner bespecification. V ing in substantially the same plane as the end of the cylinder Wall, and connection WILHELM HEFTI. 

